The noun customer is clear to all of us.
customer - *a person or an organization that buys something from a shop/store or business* - OALD
customer - *someone who buys goods or services from a business.* -MW
customer - *a person who buys - Collins
And there are many more dictionaries. Note that I'm talking about the first meaning and not the other which is referred to dealing as in A cool customer.
Now the context
The Bishop mall has a large number of footfalls everyday. However, not all of them buy. Many simply enquire about the product and go away. I could use the word 'footfall' because I'm referring to the masses. But I'm talking about one person and 'he's a footfall, not a customer' does not look correct.
My question is, what are they called? They did not buy anything. Are they merely referred to enthusiasts?
In my day-to-day language, any person who enters into the shop is a customer. As being a manager, I'd ask my salesperson, "Go, attend the customer!"
This question is not nitpicking, but there has been an actual situation like this. While discussing our friend's shop's business, I got stuck while describing that person 'X' is not a customer (won't buy anything) he's just __________.
[I know the word 'window-shopper' but it won't fit here. The person is not staring at store's windows but he actually enters, enquires, might show some interest and then go away!]
Visitors is another word that I thought of but it's very casual. It does not fulfill the qualities of customer of being enthusiastic, curious or throwing some enquiry.
Is there any term for a person who does not buy anything?
prospects
. As inprospective member/customer